1. Field of the Invention
The invention relates to a holographic neurochip, ie., opto-electronic integrated circuit (1) with a substrate surface, which generates a light pattern (2), whereby light rays emanate from some of its optically active components, light rays pass through some of its optically active components and/or light rays are reflected by some of its optically active components so as to generate the light pattern, and with a reflecting hologram which may consist of all kinds of light diffracting structures, such as, for example, reflecting binary or multilevel phase gratings, multilayered holograms, thick holograms or volume holograms, which change wave fronts impinging on them so that images of light points are generated by them alone, with additional lenses and/or additional mirrors, and that the diffraction is created by a localized change of amplitude, of the phase, of the polarization and/or a combination thereof, whereby the light pattern or parts thereof are reflected back to the substrate surface by the hologram (4).
2. The State of the Art
Hitherto opto-electronic circuits have been known which optically interconnect a predetermined arrangement of light sources and detectors utilizing one or more olograms, without, however, considering an optimum arrangement of the light sources and detectors relative to each other. This process would lead to malfunctions, if light sources and detectors are arranged in an integrated manner so that their size and distances amount to several wave lengths of the utilized light. In WO 87 06411 connections have to be formed by extremely complicated wave guides. In U.S. Pat. No. 4,705,344 the connections are formed by an array of holograms. This process allows for small apertures only, so that at a large number of connections the diffraction would result in cross-talk. Moreover, the light rays have to be deflected twice, once to the corresponding hologram element and a second time on the corresponding detector which results in an increase of cross-talk. In U.S. Pat. No. 5, 170, 269 the light rays are even deflected four or more times at similarly small apertures. In all three of the patents the modulation of the light intensities with interference is particularly critical. For that reason, coherent light sources must be used, and the entire arrangement becomes extremely temperature dependent and mechanically complex. In the present arrangement, light rays are only collected and guided to the corresponding detector, whereby with coherent light there may be areas within the surface of a detector which may experience destructive or constructive interference. While this may cause the intensity to change locally, the total sum remains always constant in accordance with the principle of energy conservation and is equal to the sum of the incident partial intensities. In addition, the light rays of all light sources impinge on a single hologram and thus emanate from the light sources, or are received by the detectors, with a large angle light cone. As a result, the aperture of this optical arrangement is particularly large, and a high resolution may be achieved.